Physics - November 2007

I have a few ceramic cups and bowls that seem to become VERY hot (hotter than the food/drink that it holds) after being zapped in the microwave.

Does this mean it has a high lead content and should I be worried about using them?

2007-11-24 18:16:05 · 3 answers · asked by Snowie 6

as i understand the newton's laws do not work at a subatomic level and i d kno why

2007-11-24 17:59:18 · 6 answers · asked by plolochufuu 2

2007-11-24 17:44:02 · 9 answers · asked by yo yo 1

Calculate the magnitude of the linear momentum for the following cases.
(a) a proton with mass 1.67 10-27 kg, moving with a speed of 5.65 106 m/s
=
????kg·m/s

(b) a 18.0 g bullet moving with a speed of 310 m/s
=??????????kg·m/s

(c) a 79.5 kg sprinter running with a speed of 10.5 m/s
=?????????kg·m/s

(d) the Earth (mass = 5.98 1024 kg) moving with an orbital speed equal to 2.98 104 m/s.
=????????? kg·m/s

2007-11-24 17:39:07 · 2 answers · asked by Dave 1

2007-11-24 17:30:44 · 6 answers · asked by arjune_00000 1

in a mixture of hydrogen and nitrogen gases at the same temperature?

2007-11-24 17:09:42 · 2 answers · asked by Chris 1

2007-11-24 17:09:13 · 19 answers · asked by gossy 2

You know the whole "no two are alike" thing? The only explanation I can come up with is "God made them" but...I want to know if there's a real reason.

2007-11-24 16:39:43 · 5 answers · asked by Anonymous

2007-11-24 16:29:49 · 1 answers · asked by Anonymous

does anyone know its formula for the final temperature?

2007-11-24 16:18:40 · 3 answers · asked by Anonymous

The active element of a certain laser is an ordinary glass rod 16 cm long and 0.7 cm in diameter. If the temperature of the rod increases by 77°C.
(a) Find its increase in length.
________cm
(b) Find its increase in diameter.
________cm
(c) Find its increase in volume.
________cm3

2007-11-24 15:53:22 · 1 answers · asked by Anonymous

2007-11-24 15:44:13 · 3 answers · asked by bigblue 2

I am trying to do my physics homework and there's a problem that asks to find the pressure inside the fluid of the hydraulic system. I am given a single mass and a single piston diameter. My only problem is that I do not know which equation to use! I have two conflicting equations (One printing in a booklet I have and the other one given by my professor in class). The one given in class is Pressure = Force / Area
and:
Pressure In = Pressure Out
so
Force1 / Area1 = Force2 / Area2

However, the booklet I have says:
Pressure1 = Pressure 2
so
Force1 * Area1 = Force2 * Area2

(Earlier in this printout it does say that pressure = force/area but that is only the pressure exerted by the fluid it states where the other is for an enclosed liquid system)

I get two drastically different answers depending on which equation I use and I do not know which one is correct! If someone could please help me that would be great!

2007-11-24 14:45:50 · 6 answers · asked by Amanda B 2

will using a 9 volt battery and using electrical wires attatched the the positive and negative side connected to two nails work as cathode protection?

2007-11-24 14:33:37 · 2 answers · asked by Speeding D 4

mass of the popper: 0.02010kg
the drop height: 1.50m
the rebound height: 1.77m (1.86, 1.81, 1.64, 1.74, 1.79, 1.76, 1.75, 1.78)
the height of bounce when the popper is not turned inside out: 0.678m(0.65, 0.66, 0.82, 0.58)
E= m*g*h
please answer the qustions plz its urgent
question: determine:
-the gravitational potential energy at its highest point (after hitting the ground)
-the kinetic energy of the popper just before landing(hint: consider where the kinetic energy is being transffered from)
-approximately how much energy is stored as elastic potential energy before the popper flips(hint what other amount of energy that you have calculated could you use to determine this? Of that amouunt how much energy has been lost?"
-the total energy of the popper (at any point of its motion)
-if mechinical energy is conserved

3) what is reasonable estimate for the amount of nergy that is lost due to friction sound?
4) how much work is done in flipping the popper inside out?

2007-11-24 14:00:20 · 1 answers · asked by Anonymous

I heard that if an object reflected light wave, we will see the color, depends on the light wave. But some materials, like glass and water, just let the photon go through.

But, how can we know if the photon is reflected or just go through? Both happen when the electrons don't need the energy to move to another energy level.

Please explain as clear as possible and use simple vocabulary. Sorry about my poor English.

Thanks in advance.

2007-11-24 13:50:53 · 1 answers · asked by ? 6

2007-11-24 13:43:18 · 9 answers · asked by AirGear/GSD Fan 1

2007-11-24 13:09:22 · 1 answers · asked by maria lorna d 1

Where eta is the viscosity of the fluid, L is the length of the tube, and r is the radius of the tube.

Also, if you can just derive it, that would be awesome.

Thanks!

2007-11-24 12:57:00 · 1 answers · asked by frogster99 2

As in, a good pour would result in all water going into whatever you're pouring into. What I'm talking about is when it runs down the side and then into what you're trying to pour the liquid into.

2007-11-24 12:52:16 · 8 answers · asked by la_runner_w 1

Which cup will be cooler after a few minutes?

2007-11-24 12:51:12 · 3 answers · asked by summersun 1

2007-11-24 12:30:01 · 5 answers · asked by blueyedbabe_91 3

Why not tiny vibrating cubes or blobs?

2007-11-24 12:26:09 · 3 answers · asked by Anonymous

2007-11-24 11:38:37 · 5 answers · asked by AirGear/GSD Fan 1

Weight comes from gravity force pulling down, But what about mass? Is it still mystery question that still hasn't been solved?

2007-11-24 11:29:06 · 6 answers · asked by Tobiko x) 1

2007-11-24 11:15:28 · 2 answers · asked by jamie 1

Is it just me or does it seem like you can look at objects longer then people? This always happens to my friends and I. So why can you look at objects longer then people?

2007-11-24 11:05:32 · 5 answers · asked by Katara 1

2007-11-24 10:44:07 · 2 answers · asked by Jenny D 1

I have a lightbulb in my restroom that is burned out. Does it burn more electricity when the switch is on than it does when it is off?

2007-11-24 10:33:11 · 10 answers · asked by Red 2

and without going around the wall.

2007-11-24 10:23:42 · 4 answers · asked by rowdylaude 1